Hi,
How are you? Was there trauma previously? Are there other symptoms present like fever, eye pain or visual changes? Swelling or edema may be caused by sinus infection, soft tissue pathology and possible Pott's puffy tumor which should be ruled out by CT scan or MRI. Have this checked by a neurologist and imaging studies be done for proper evaluation.Take care and do keep us posted.
Is the swelling obvious? Meaning, is it something you are feeling from the inside, like the forehead is too tight or is it a visible swelling from the outside? Are you taking anything for the pain? If you are taking over-the-counter meds you could be suffering from rebound headaches. I was unaware of this myself until this past year. I would have headaches a few times a day, every day. I was taking ibuprofen, 4 at a time, 3-4 times a day. This would help the immediate pain but the headaches would return, becoming more and more painful.
Just something to consider. Not sure what could be causing the swelling but think I might ask for some tests if it continues. May be from inflammation or edema.
TC